Snap slit door with over pressure relief

ABSTRACT

A snap slit door having at least one panel and a flat closure means used toreate tension in the door panel or panels, such tension acting as the closure force generated by the closure means for the door panel or panels. The flat closure means may be adjustable such that the tension and resulting resistance to opening is variable. Said door panel or panels may be of any pliable material to enable use of the panel or panels without hinges, and further to render the flat closure means operational. The panel or panels may be held in the closed position by any means which will self-release upon the exertion of a requisite pressure differential between the inside and outside of the panel or panels, effectively relieving the pressure differential. One such effective self-releasing closure means is a hook and pile patch arrangement.

GOVERNMENT INTEREST

The United States Government has rights in this invention pursuant tocontract No. DAAK-11-80-C-0030 awarded by the Department of the Army.

BACKGROUND OF THE INVENTION

This invention relates generally to doors, door panels and door closuremeans. Many types of doors are known in the prior art; most utilize ahandle, a locking mechanism in combination with the handle, and a pairof hinges. Additionally, several other non-essential elements may beutilized, such as a latch, a self-closing mechanism, a window orwindows, as well as other components occasionally incorporated into thedoor. Because of the multitude of moving and non-moving parts, andbecause of the wide variety of functions which doors are expected toserve, doors are found to exist in infinite variety, each suited to agiven set of specific needs.

Doors containing one or a plurality of panels have been used whereinsaid panels may be comprised of many different materials. Representativeexamples of materials from which door panels have been made includewood, metal, cloth, plastic, and similar substances. The substance fromwhich such door panels are made is chosen depending upon the functionsthat each panel is to serve. For example, the material comprising eachpanel is frequently chosen to provide a secure closure means or to serveas a decorative and durable security device. Alternatively, a panelcomprised of screen material can be used where privacy is not requiredand adequate ventilation is a necessity. Frequently a pair of panels isused, wherein one panel is comprised of any pliable substance, and asecond is comprised of a screen. As such, the combination is useful toprovide privacy, and adaptable to provide adequate lighting and/orventilation. Various sizes and shapes of panels have been utilized,depending upon the size of the object passing through the door, theoverall dimensions of the system in which the door is contained, thefrequency of use, and the durability desired.

Similarly, closure means have been comprised of a variety of materials,including springs, self-closing hinges, pulley means, and mechanicalmeans. The means for closing doors in the prior art have typically beenbulky or burdensome, requiring the user to close the door manually or toactivate a complicated mechanical device to close the panels.Additionally, such closure means and doors did not open and closequickly to permit fast ingress and egress cycles. Further, such priorart doors and closure means typically did not operate to permit safeequalization of pressure found on both sides of the door, when thepressure differential between sides was extremely great. Rather, atremendous pressure differential between the sides of a door placedstress and strain upon the material of the door panel, the hinges, theclosure mechanism and the locking mechanism. Finally, breakage of one ofthe above-mentioned components occurred, allowing the pressure toequalize.

SUMMARY OF THE INVENTION

Applicant's invention provides for a door with at least one panel and aflat closure means used to create tension in the door panel or panels,such tension acting as the closing force generated by the closure meansfor the door panel or panels. Additionally, the invention encompasses aflat closure means which is adjustable in its attachment to the doorpanel or panels and in its tensional resistance. Using a flat closuremeans in this manner allows the user to adjust the tension runningthrough the door panel or panels, and as such, a flat spring may be usedto create tension through the door panels in more than one door.Applicant's invention does not require the use of hinges, therebyeliminating mechanical parts, as required in the prior art.

OBJECTS OF THE INVENTION

Accordingly, it is one object of this invention to provide an enclosureencompassing a door with at least one door panel which enables ingressand egress by merely holding the panel or panels in an open position,and passing through the opening.

Further objects of this invention include an enclosure encompassing adoor comprised of any pliable material to allow fast ingress and egresscycles, eliminate the requirement for hinges, have fewer moving partsand not injure a person or damage material passing through the openingof the door if such person or material comes into contact with the door.

A further object of this invention is to provide a door comprised of atleast one panel, thereby enabling a user or object to create an openingbetween the panel and the door frame or between two panels and to passthrough the opening.

A yet further object of this invention is to provide an enclosureencompassing a door which need not be mounted on hinges, therebyreducing the number of moving parts involved, and for such a door tofurther comprise a side wall of a container, thereby enabling a personor an object to pass into or out of a container.

The preferred embodiment of Applicants' invention as disclosed hereinwill be described in greater detail below with reference to thedrawings, wherein:

FIG. 1 is a front prespective view of the snap slit door;

FIG. 2 is cross sectional view of the panels of the snap-slit door, asseen from line 2--2 in FIG. 1; and,

FIG. 3 is an exploded view of the preferred embodiment of Applicants'invention, utilizing a pair of snap slit doors;

FIG. 4 shows a detail view of the closure system;

FIG. 5 shows details of the door-to-leaf spring attachment.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring in detail to the drawings, Applicants' invention encompasses adoor designated generally as 10, having at least one panel 11 and a flatclosure means 14.

The panel or panels 11 utilized in Applicants' invention are typicallymade from any pliable material. Pliable material is preferred to enablethe panels to be spread by the user to an open position, therebyallowing ingress and/or egress. When a single panel is used the pliablenature of the door panel is useful for enabling the single panel 11 tobe held in its open position apart from the door frame (not shown), forsimple ingress and/or egress. Any such pliable material may be utilizedwhich provides the user with the preferred properties in the door 10.For example, a waterproof material may be utilized to prevent moistureor dampness from permeating the material contained within and protectedby the inside of the door panel 11 or panels, or from rendering a personprotected by the panel 11 wet and uncomfortable. If desired, anyplastic, cloth, canvas, rubber or similar material may be used forwaterproof paneling. Alternatively, a non-waterproof material such as acotton-type cloth coated with a rubber or plastic compound or a sealantmay be suitable to prevent moisture from permeating the protected area.

The panel or panels 11 typically are attached to a rigid member 17, thepoint of attachment serving as a portion of the overall support for eachpanel 11, similar to a door frame and hinge mechanism. Said rigid member17 may be enclosed within the confines of a system, as shown generallyin FIG. 1. Alternatively, rigid means 17 may be directly adjacent to thepanels 11 and located outside of the confines of the enclosed system, asshown generally in FIG. 3. However, it is to be understood that rigidmember 17 should either be unattached to the panel or panels 11 at thetop, or may be sufficiently bendable so as to enable the panel or panels11 to assume an open position when held in the open position duringingress or egress. Attachment of the panel or panels 11 at the uppermostportion of the rigid member 17 limits the utility of Applicants'invention by greatly reducing the extent to which panel or panels 11will assume an open position.

In the preferred embodiment of Applicant's invention, a pair of panels11 is further described as comprising an outside panel 18 and an insidepanel 19. It is to be understood, however, that the designations"outside" and "inside" refer to panel overlapping region 13 rather thanthe entire surface of each panel 11. The dimensions of the paneloverlapping region 13 are variable within wide limits, depending uponthe size of the panels 11, and placement of the rigid member 17supporting each panel 11. For example, outside panel 18 having an outeredge 12 may overlap the inside panel 19, having an inner edge 16 byapproximately two (2) inches, generally creating a panel overlappingregion 13 two inches wide and running essentially for the entirevertical length of said panels 11. Alternatively, the pair of panels 11may each be hung from a rigid support member 17 so as to cause therespective panels to overlap in a panel overlapping region 13 which doesnot run essentially the length of said panels 11. Rather, panels 11 mayeach be supported by a rigid member 17 so as not to overlap, or tooverlap on angle, if rigid support members 17 are not positionedparallel to each other.

A flat closure means 14 is used to place tension upon panels 11, and tokeep panels 11 in a stable position in relation to one another byattaching to the outside panel 18 and/or to the inside panel 19. Theflat closure means may optionally be attached to either or both suchpanels 11 within the confines of the panel overlapping region 13.Attachment in this manner provides tension through the material of eachpanel 11, primarily at the outer panel edge 12 and inner panel edge 16of each respective panel 11, as well as through each panel in theoverlapping region 13. Preferably, flat closure means 14 is in the shapeof a spring, such as a flat leaf spring, bearing sufficient strength toprovide adequate tension through panels 11, and causing such panels 11to return to their closed position after being manually separated foringress and/or egress. Such a flat leaf spring may provide foradjustment of the tension embodied in each panel 11, or of the tensionalstrength of said flat leaf spring, which, in turn adjusts the tension ineach panel 11.

Further, the flat leaf spring attached to the panel or panels 11functions as a self-closing mechanism and as an overpressure reliefsystem. When a container with the snap slit door 10 therein developsinternal pressure sufficiently greater than the atmospheric pressuresurrounding the container, such internal overpressure causes panels 11to separate at panel overlapping region 13, thereby allowing saidexternal and internal pressure to equilibrate. The pressure at whichsaid panels 11 will separate is dependent upon the rigidity and/ortensional strength of the flat closure means 14, the tension bourne byeach of the panels 11 and the resistance to overpressure relief providedby a securing means 15.

To further provide resistance to internal and external pressureequilibration, and to essentially maintain the panels 11 in a closedstate, Applicant's invention further encompasses a securing means 15.Securing means 15 can be any means useful for securing the outside panel18 to the inside panel 19, or the panel 11 to rigid member 17. As such,a hook and pile patch, commonly known as Velcro® is ideal. Alternativesecuring means 15 are possible and within the scope of this invention,and include snaps, buttons and similar devices which will unfasten whena significant overpressure differential develops.

To utilize Applicant's invention for ingress and/or egress, the outeredge 12 of the outside panel 18 and the inner edge 16 of the insidepanel 19 may be grasped or otherwise physically separated to hold saidpanel or panels 11 in an open position, so that an object or individualmay pass through the opening created between the panels 11. Opening thepanels in this manner increases the tension on said panels 11 in thepanel overlapping region 13, caused by bending the flat closure means14. When the respective edges of the outside and inside panels 18 and 19are released, the flat closure means 14 returns to its normal position,thereby causing the panels 11 to close automatically upon such release.While the preferred embodiment of Applicants' invention utilizesvertical panels 11 which serve to define a vertical slit between thepanels 11, it is possible and within the scope of Applicants' inventionto utilize the panels 11 in a horizontal position, which then define ahorizontal slit between them.

Similarly, it is possible and within the scope of Applicants' inventionto utilize mulitple sets of panels 11 to define multiple snap slip doors10 as shown generally in FIG. 3.

FIG. 4 illustrates the spring arrangement in more detail. It isexplained that doors 11 and 12 are actually made of cloth fabric orcarpeting or the like in one embodiment for the closure means. It isused as an airlock (antechamber) for entry into a main building which ismeant to be isolated from the outside environment, as for one examplefrom the dust in the outside world. After one enters this antechamberand the front doors close back behind him, then the chamber can bepumped out, to remove contaminants in the atmosphere. After everythingis satisfactory, then the person can go out the back doors of thisantechamber, and on into the main building where, for example,semiconductors may be under manufacture in a dust free enviroment.Another possible use is for a hospital operating room entry means.

As the person enters this antechamber by spreading the fabric pieces, 11and 12 into an area, he is actually pulling down on leaf spring 14,which itself is attached to the ceiling frame. He may use a handle if hewishes. The pulling action is because the fabrics are held sandwiched inby (aluminum or other) piece 106 (which could run the whole width of thefabrics, or less if desired), through which is also riveted (orotherwise connected) to the leaf spring. The spring, it is explained, isa flat piece of steel (or other springy material) which is curved at itsend (or bent 90° such as at corner 105) to provide an end surface forattachment to said fabrics. The fabrics are firmly attached all alongtheir base areas (to, for example, the base frame of the enclosure).Since the fabrics 11 and 12 are arranged to be completely taut beforethey are spread open, the opening action actually translates into a"pulling down" action upon the leaf spring. Once the person releases thefabrics, as when already inside, the leaf spring causes the fabrics toresume their taut position again. A version of FIG. 4 has beensuccessfully used under a development program by the inventors herein.FIG. 5 shows part 106 in more detail, as connected to leaf spring andcloth doors. Pieces 105 and 106 may be of one piece; rivetting 107 maybe replaced by other attachment methods. A perfect 90° bend on spring 14is also not necessary.

While Applicants have described what is believed to be the preferredembodiment of their invention, other alternative embodiments will beobvious from the teachings herein. Consequently, the scope ofApplicants' invention is not to be limited hereby.

What is claimed is:
 1. A snap slit door comprising:at least one panelhaving an edge; a rigid member attached to each panel opposite the edge;and a flat closure means attached to at least one panel adjacent theedge.
 2. The snap slit door of claim 1 further comprised of an insidepanel and an outside panel.
 3. The snap slit door of claim 1 wherein theflat closure means is further comprised of a flat spring.
 4. The snapslit door of claim 3 wherein the flat closure means is further comprisedof a flat leaf spring.
 5. The snap slit door of claim 4 wherein the flatleaf spring is adjustable.
 6. The snap slit door of claim 5 wherein theflat closure means is attached to the inside panel and the outsidepanel.
 7. The snap slit door of claim 5 wherein the flat leaf spring isadjustable to provide overpressure relief.